Though we think of dinosaurs as being extinct, recent research suggests that their modern relatives live among us in the form of birds. Like birds, many dinosaurs built nests, laid eggs, and had feathers. Over the last twenty years, scientists have collected more and more evidence suggesting that dinosaurs evolved into birds. For example, thousands of fossils of dinosaurs with feathers have been found in China, and fossil dinosaur eggs are similar in size and shape to birds’ eggs. Fossils have also revealed information about dinosaurs’ skeletons. Birds have hollow bones to enable flight, and did some dinosaurs. In addition, birds and dinosaurs exhibit many similarities in their legs, feet, and claws.
What is the main, or central, idea of the passage?
Fossil evidence shows that some dinosaurs had hollow bones, which probably enabled them to fly.
Fossil evidence shows that dinosaurs and birds share many features, suggesting that they are related.
Fossil evidence shows that the legs, feet, and claws of dinosaurs and birds are similar.
The correct answer is: Fossil evidence shows that dinosaurs and birds share many features, suggesting that they are related.
Explanation: The passage discusses various similarities between dinosaurs and birds, including feathers, nesting behaviors, egg characteristics, and skeletal features, particularly how these similarities indicate a connection between the two groups. The other options focus on specific details rather than the main idea of their relationship.